Minolta EP1030 - Developing Unit and ATDC Sensor; ATDC Sensor Operation; ATDC Sensor Automatic Adjustment

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11595BM0700A
Y@ DEVELOPMENT
The Developing Unit built into the Imaging Unit performs the following functions:
e Mixes the toner and carrier weil to ensure that a sufficient amount of toner is
positively charged.
e Detects the toner-to-carrier ratio of the developer by means of the ATDC Sensor
and replenishes the supply of toner as necessary.
e Detects a toner empty condition by means of the ATDC Sensor.
e Ensures that a proper amount of toner is attracted to the PC Drum by means of
its Sleeve/Magnet Roller, Developing Bias, and Doctor Blade.
2nd Developer
Mixing Screw
Doctor Blade
ATDC Sensor
1159M003AA
Sleeve/Magnet Roller 1 st Developer
Mixing Screw
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1159SBM0701 A
7-1. ATDC Sensor
ATDC Sensor UN3 installed on the underside of the Developer Mixing Chamber
detects the varying toner-to-carrier ratio of the developer which flows over it in the
Chamber. The copier CPU compares the detected ratio with the ratio set by the
ATDC Detection Level Mode (Tech. Rep. Choice SCH-90) to control toner
replenishment.
Set T/C (%) ATDC Output Voltage (V)
CC
50 2.48 (Standard)
ss awSC=*”
Caen C3] ene
The Toner Bottle is turned one turn (30 mg) to replenish the supply of toner for each Toner
Replenishing signal.
If the toner-to-carrier ratio becomes lower than 2.5%, the copier inhibits the initiation
of a new copy cycle (this feature can be enabled or disabled by a Tech. Rep. Choice
function). When a ratio of 2.5% or more is recovered as a result of Auxiliary Toner
Replenishing, the copier permits the initiation of a new copy cycle.
If the Front Door is swung open and closed with aT/C ratio of less than 4%, the copi-
er initiates an Auxiliary Toner Replenishing sequence. (It stops the sequence as
soon as a T/C ratio of 5% is reached.)
ATDC Sensor Automatic Adjustment
An automatic adjustment of the ATDC Sensor is made in the F8 Test Mode
operation and when a new Imaging Unit is installed in the copier.
*When a New Imaging Unit is Installed in the Copier:
Following the execution of the starter setup mode upon power-up, the copier
CPU reads the output value of the ATDC Sensor and establishes the reading
as the reference value.
*When F8 is Run after Starter Has Been Changed:
Following the execution of the starter setup mode upon pressing of the Start
Key, the copier CPU reads the output value of the ATDC Sensor and establishes
the reading as the reference value.
NOTE: if an F8 operation is run at a time when the starter has not been changed,
it can result in a wrong T/C reference value being set by the copier. Avoid
casual use of F8.
If the setting value has been cleared because the RAM Board was
replaced, set the value valid before the replacement for the ATDC Sensor
adjustment data of the Adjust mode using the 10up/Tup key.
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